Seaweed invasion impacts SC coast, economy

A seaweed invasion on the Carolina coast has researchers questioning the harm it may or may not have on the environment and economy and it could be detrimental.

They look like the hair on your head.

Gracilaria

“Seaweeds have taken over the mudflats in our harbors and are blooming off shore,” says College of Charleston Researcher Erik Sotka.

Sotka says there are two types of invasive seaweeds they have found.

“One is called polysiphonia from the Mediterranean originally and it goes in a boom-and-bust cycle. The second is called gracilaria and that one’s from Japan, and it’s in-shore basically smothering our mudflats,” says Sotka.

Mudflats provide much of the base of the food web. Sotka and other reasearch engineers, like Loren Danese, have set up cages made of chicken-wire in the water to test these seaweeds and find out the impacts they may have.

“Wanna see if the worms will attach the gracilaria that we put in and also if

Erik Sotka and gracilaria

they’ll attach to the fake gracilaria that we put in to see if they just like that structure there,” says Danese.

Sotka says the seaweeds on the mudflats are attached to worm tubes and remain still, but the seaweed more off-shore act as tumbleweeds. He says they have two types of impacts.

“It’s clogging the nets of shrimpers and it’s clogging the crab pots, so there’s a direct economic cost. And then it impacts the smaller shrimps, the smaller crabs, the smaller clams, that are the food source for things we like to eat,” says Sotka.

Sotka says there is no sign of any health risks from these seaweeds. They are currently conducting studies to find out the exact impacts the seaweeds have.

Researchers do not expect these two invasive seaweeds to leave the coast, they just want to minimize the amount.